Is there a reason that zvláštní ends on í and not on ý like many other adjectives?
There are "hard adjectives" and "soft adjectives," and they behave somewhat differently. See, for example, the Tips & Notes here: https://www.duolingo.com/skill/cs/Masculine/tips-and-notes.
I read the tips and notes in the meantime, I didn't even see that was there! Thank you for the response though, I've been enjoying learning some Czech.
You can find the T&N by selecting a Skill, and then clicking on the light bulb icon; if there's no light bulb, T&N don't yet exist for that Skill. NOTE: T&N are currently available only on the web (desktop or mobile), not in the apps.
I've found them to be extremely helpful so far, especially with pronounciation of certain letters.
Because that is the translation of word strange=divný, podivný, zvláštní, špatný is wrong or bad.
In some context strange and wrong may mean the same, but for a tree? I don't think so.